Physiological Adaptation of Habitat by Ion Distribution in the Leaves of Four Ecotypes of Reed (Phragmites australis)

The ion levels in the epidermal bulliform cells of epidermis, mesophyll cells and cells of the vascular bundle sheath of four ecotypes of reed (Phragmites australis (Cav.) Trin. ex Steud.) were determined by means of X_ray microanalysis. The results indicated that higher K +, Na +, Ca 2+ , Mg 2+ and Cl - were distributed in the vascular bundle sheath cells than in mesophyll cells and epidermal bulliform cells of the swamp ecotype. Higher Ca 2+ was found in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, higher Mg 2+ in the mesophyll cells and higher K +, Na + and Cl - in the vascular bundle sheath cells of the dune ecotype. Higher Na + and Mg 2+ was determined in the mesophyll cells than in the bulliform cells and vascular bundle sheath cells, and higher K +, Ca 2+ and Cl - in the vascular bundle sheath cells of the light salt meadow ecotype. In the heavy salt meadow ecotype, higher Na + and Mg 2+ were accumulated in the bulliform cells than in mesophyll cells and vascular bundle sheath cells, but higher K +, Ca 2+ and Cl - in the mesophyll cells. Furthermore, the distributional conditions of the above five ions in leaf cells of the four ecotypes and their significance in the physiological adaptation of reed to habitat were discussed in detail.

Effects of Adaptation to Elevated Salinity on Some Enzymes' Salt_tolerance in Vitro and Physiological Changes of Eelgrass

The eelgrass ( Zostera marina L.) was treated with artificial seawater (ASW) of different salinities ( 100%, 150% and 200% seawater) for 5 d. The activities of two enzymes extracted from the plant leaves were determined under a salinity grade in vitro So were the photosynthesis rates of the plants from the three treatments in the media with different salinities 100%, 150%, 200%, 300% ASW) and Some physiological data. The data showed that under increased salinities (concentrated seawater), Na+, Cl-, MDA (malon dialdehyde) and glucose contents and the osmotic potentials ( absolute value) in the leaves increased with the salinity elevation in the medium (ASW), but both K+ and free amino acid (mainly proline) contents decreased. Malate dehydrogenase (MDH) from the plant leaves under a salinity grade showed its activities (A) as follows: A(100%) (ASW) > A(150%) (ASW) > A(200%) (ASW). Phosphoenolpyruvate carboxylase (PEPC) extracted from the 100% ASW- and 200% ASW-treated plants showed similar activities (both insensitive to salinities) under the salinity grade in vitro, but the activities of PEPC from plants treated with 150% ASW were dependent oil salinity. Whether the plant is stressed at 150% ASW and can stand higher salinity than seawater needs to be studied further. Meantime, die data do not agree with the opinion that the adaptation of the eelgrass to seawater salinity is partly fulfilled by its insensitiveness to salinities in Some metabolic enzymes. It can be inferred that the lack of transpiration may be an important aspect of tire plant's tolerance to seawater salinity.

Transcriptomic and physiological analyses identifying Lanzhou lily(Lilium davidii var.unicolor)drought adaptation strategies

Drought stress is the main limiting plant growth factor in arid and semiarid regions.The Lanzhou lily(Lilium davidii var.unicolor)is the only sweet-tasting lily grown in these regions of China that offers highly edible,medicinal,health,and ornamental value.The Tresor lily is an ornamental flower known for its strong resistance.Plants were grown under three different drought intensity treatments,namely,being watered at intervals of 5,15,and 25 d(either throughout the study or during specific growth stages).We measured the biomass,leaf area,photosynthetic response,chlorophyll content(SPAD value),and osmoregulation of both the Lanzhou lily and the Tresor lily(Lilium‘Tresor’).Additionally,we employed RNA sequencing(RNA-Seq)and qRT-PCR to investigate transcriptomic changes of the Lanzhou lily in response to drought stress.Results showed that under drought stress,the decreasing rate in the Lanzhou lily bulb weight was lower than the corresponding Tresor lily bulb rate;the net photosynthetic rate,transpiration rate,and stomatal conductance of the Lanzhou lily were all higher compared to the Tresor lily;osmoregulation constituents,such as glucose,fructose,sucrose,trehalose,and soluble sugar,in the Lanzhou lily were comparatively higher;PYL,NCED,and ERS genes were significantly expressed in the Lanzhou lily.Under moderate drought,the biosynthesis of flavonoids,circadian rhythms,and the tryptophan metabolism pathway of the Lanzhou lily were all significant.Under severe drought stress,fatty acid elongation,photosynthetic antenna protein,plant hormone signal transduction,flavone and flavonol biosynthesis,and the carotenoid biosynthesis pathway were all significant.The Lanzhou lily adapted to drought stress by coordinating its organs and the unique role of its bulb,regulating photosynthesis,increasing osmolyte content,activating circadian rhythms,signal transduction,fatty acid elongation metabolism,and phenylalanine and flavonoid metabolic pathways,which may collectively be the main adaptation strategy and mechanisms used by the Lanzhou lily under drought stress.

Morpho-Physiological,Biochemical and Molecular Adaptation of Millets to Abiotic Stresses:A Review

Abiotic stresses such as drought,heat,cold,nutrient deficiency,excess salt and hazardous metals can hamper plantgrowth and development.Intensive agriculture of only a few major staple food crops that are sensitive and intolerant to environmental stresses has led to an agrarian crisis.On the other hand,nutritionally rich,gluten free and stress tolerant plants like millets are neglected and underutilized.Millets sustain about one-third of the world’s population and show exceptional tolerance to various abiotic and biotic stresses.Millets are C4 plants that are adapted to marginal and dry lands of arid and semi-arid regions,and survive low rainfall and poor soils.Abiotic stresses significantly affect plant growth which ultimately results in reduced crop yields.However,various adaptation mechanisms have evolved in millets to withstand different stresses.This review aims at exploring various of these morphophysiological,biochemical and molecular aspects of mechanisms in millets.Morphological adaptations include short life span,smallplant height and leaf area,dense root system,adjusted flowering time,increased root and decreased shoot lengths,high tillering,and leaf folding.A high accumulation of various osmoprotectants(proline,soluble sugars,proteins)improves hyperosmolarity and enhances the activity of antioxidant enzymes(e.g.,Ascorbate peroxidase,Superoxide dismutase,Catalase,Peroxidase)providing defense against oxidative damage.Physiologically,plants show low photosynthetic and stomatal conductance rates,and root respiration which help them to escape from water stress.Molecular adaptations include the upregulation of stress-related transcriptional factors,signalling genes,ion transporters,secondary metabolite pathways,receptor kinases,phytohormone biosynthesis and antioxidative enzymes.Lack of genetic resources hampers improvement of millets.However,several identified and characterized genes for stress tolerance can be exploited for further development of millet resilience.This will provide them with an extra characteristic plant resistance to withstand environmental pressures,besides their excellent nutritional value over the conventional staple crops like rice,wheat and maize.

Taste Adaptation of Helicoverpa armigera Larvae to Azadirachtin and Its Physiological Mechanism

Dual-choice behavioral assays and electrophysiological tip-recording technique were used to investigate the taste adaptation of different diet-experienced frith instar larvae of Helicoverpa armigera to azadirachtin. The behavior test showed that the larvae reared with normal artificial diets were highly deterred by aza- dirachtin. However, the larvae reared with the artificial diets containing low concentration of azadirachtin showed insensitivity to asadirachtin. The electrophysiological tests showed that there was a changed responsiveness in the deterrent neuron responding to asadirachtin in the lateral sensilla styloconica of different diet-experienced larvae. It indicated that there was a taste adaptation to azadiraehtin in different diet-experienced larvae of H. armigera and this taste adaptation was correlated with desensitization of related taste neurons.

Changes in embryonic development,juvenile growth and physiological adaptation of the cuttlefish Sepia pharaonis in response to photoperiod manipulation

Photoperiod is a key environmental indicator for re gulating embryonic development,individual growth and physiological processes in aquatic animals.In this study,differences in embryonic development and performance of newly hatched cuttlefish juvenile exposed to five different cycles of light:dark(L:D):constant light,18 L:6D,12 L:12D,6 L:18D cycles,and constant darkness were evaluated.Prolonged exposure to light induced an accelerated rate of embryonic development,particularly after the red-bead stage.Principal component analysis(PCA)revealed that red-bead stage,heartbeat,endoskeleton formation,pigment appear,and six increments of cuttlebone were the main factors contributing to the embryonic development.Meaning that the duration time of these five stages were significantly different when exposed to photoperiod regimes,which may determine the duration of the incubation period of the embryos.Long term light has also affected the incubation parameters with an increased rate in hatching and shortened the incubation and hatching periods in the 12-24-h day length range.However,constant light and darkness environment appeared to have a greater effect on the stress of embryonic development,mainly reflected in the yolk shed ratio and the inking rate in the egg capsule.Moreover,the increase in the day length has contributed to improve the growth and survival of juveniles in the 12-18-h day length range;however,juveniles exposed to constant light and darkness experienced worse re sults in terms of growth,tissue glycogen content,dige stive enzymes of the digestive glands,and metabolic enzymes of the muscles.These finding suggest that prolonged light exposure accelerates the process of embryonic development,maximum feeding time is not necessarily a condition of optimal growth,and inappropriate light cycles can disturb the body’s endogenous controls.Therefore,the optimal photoperiod for the embryos development and juvenile growth of Sepia pharaonis were 12 h and 12-18 h of day length,respectively.These results are useful for increasing the production of this species during embryo incubation and juveniles rearing in aquaculture practice.

Physiological, Anatomical, Psychological and Cultural-Ethnic Aspects of Indian Students Adaptation during Study in Kyrgyzstan Medical Universities

This article is investigating the comparative analysis of anatomical, physiological, and psycho-emotional adaptation indicators of 100 male and 100 female first-year students of the international medical faculty in Osh, Kyrgyzstan. Control groups have consisted of 100 male and 100 female local students of the same age, residing in the Osh city and region. Anthropometry is determined by 50 indicators, such as bio-impedance analysis of body composition, functional tests with exercise, and breathe holding. In addition, the girls underwent an assessment of sexual development according to Tyner. The psychological state was assessed using the Lüschers color test and Spielberger’s questionnaire. The features of anthropometric indicators for students from India are shown as a shorter length of the body, shoulder, and legs, greater waist coverage, an increase in the thickness of the skin folds of the abdomen, increased fat mass and delayed sexual development, anxiety, frequent and longer colds. Functional tests for breath holding and physical activity revealed less reserve capacity in foreign students. This requires the development of rehabilitation programs for foreign students, starting from the first year.

Genome-wide association study dissecting drought resistance-associated loci based on physiological traits in common bean

Genetic improvement of drought resistance is one of the main breeding goals for common bean,so molecular markers must be identified to facilitate drought resistance breeding.In this study,we evaluated the proline,trehalose,raffinose,and stachyose contents of 210 common bean accessions under two watering conditions and found large variations in all four.The coefficients of variation ranged from 21.21%for proline content to 78.69%for stachyose content under well-watered conditions,and from 20.11%for proline content to 50.08%for trehalose content under drought stress.According to our genome-wide association analysis,32 quantitative trait loci were associated with drought resistance,seven of which overlapped with known loci.Four hotspot regions were identified at Pv01,Pv07 and Pv11.A set of candidate genes was identified,including genes encoding MYB,bZIP,bHLH,ERF,and protein kinases.Among these genes,Phvul.001G189400,Phvul.007G273000 and Phvul.008G270500 were annotated as bZIP,ERF and WRKY,respectively.These genes are reportedly involved in drought stress responses in Arabidopsis thaliana and were induced by drought stress in common bean.Significant SNPs in six candidate gene regions formed different haplotypes,and phenotypic analysis revealed significant differences among the haplotypes.These results provide new insight into the genetic basis of drought resistance in common bean and reveal candidate genes and superior natural variations that will be useful for improving common bean.

Seed Storability in Rice: Physiological Foundations, Molecular Mechanisms, and Applications in Breeding

Long-term storage of crop seeds is critical for the conservation of germplasm resources, ensuring food supply, and supporting sustainable production. Rice, as a major food staple, has a substantial stock for consumption and production worldwide. However, its food value and seed viability tend to decline during storage. Understanding the physiological responses and molecular mechanisms of aging tolerance forms the basis for enhancing seed storability in rice. This review outlines the latest progress in influential factors, evaluation methods, and identification indices of seed storability. It also discusses the physiological consequences, molecular mechanisms, and strategies for breeding aging-tolerant rice in detail. Finally, it highlights challenges in seed storability research that require future attention. This review offers a theoretical foundation and research direction for uncovering the mechanisms behind seed storability and breeding aging-tolerant rice.

Advances in Wireless,Batteryless,Implantable Electronics for Real‑Time,Continuous Physiological Monitoring

This review summarizes recent progress in developing wireless,batteryless,fully implantable biomedical devices for real-time continuous physiological signal monitoring,focusing on advancing human health care.Design considerations,such as biological constraints,energy sourcing,and wireless communication,are discussed in achieving the desired performance of the devices and enhanced interface with human tissues.In addition,we review the recent achievements in materials used for developing implantable systems,emphasizing their importance in achieving multi-functionalities,biocompatibility,and hemocompatibility.The wireless,batteryless devices offer minimally invasive device insertion to the body,enabling portable health monitoring and advanced disease diagnosis.Lastly,we summarize the most recent practical applications of advanced implantable devices for human health care,highlighting their potential for immediate commercialization and clinical uses.

Physiological Mechanism of Exogenous Selenium in Alleviating Mercury Stress on Pakchoi(Brassica campestris L.)

The objective of this study was to explain the physiological mechanisms through which Na_(2)SeO_(3) mitigates the growth and developmental inhibition of pakchoi under HgCl_(2)stress.The results showed that treatment with HgCl_(2)(40 mg L^(−1))led to reduced biomass,dwarfing,root shortening,and root tip necrosis in pakchoi.Compared to control(CK),the activities of superoxide dismutase(SOD)and peroxidase(POD)in Hg treatment increased,and the content of malondialdehyde(MDA)also dramatically increased,which negatively impacted the growth of pakchoi.Low concentrations of Na_(2)SeO_(3)(0.2 mg L^(−1))significantly increased the content of soluble sugars compared with control,while chlorophyll,soluble proteins,free amino acids,and vitamin C had no significant changes.The results of the mixed treatments with HgCl_(2)and Na_(2)SeO_(3) suggested that selenium may be able to reduce the toxicity of mercury in pakchoi.The biomass,plant height,root length,chlorophyll content,soluble protein,other physiological indicators,and proline showed significant increases compared with the HgCl_(2)treatment.Additionally,the MDA content and mercury accumulation in pakchoi decreased.Our results revealed the antagonistic effects of selenium and mercury in pakchoi.Thus,a theoretical basis for studying pakchoi’s mercuryexcreted and selenium-rich cultivation technology was provided.

Artificial intelligence in physiological characteristics recognition for internet of things authentication

Effective user authentication is key to ensuring equipment security,data privacy,and personalized services in Internet of Things(IoT)systems.However,conventional mode-based authentication methods(e.g.,passwords and smart cards)may be vulnerable to a broad range of attacks(e.g.,eavesdropping and side-channel attacks).Hence,there have been attempts to design biometric-based authentication solutions,which rely on physiological and behavioral characteristics.Behavioral characteristics need continuous monitoring and specific environmental settings,which can be challenging to implement in practice.However,we can also leverage Artificial Intelligence(AI)in the extraction and classification of physiological characteristics from IoT devices processing to facilitate authentication.Thus,we review the literature on the use of AI in physiological characteristics recognition pub-lished after 2015.We use the three-layer architecture of the IoT(i.e.,sensing layer,feature layer,and algorithm layer)to guide the discussion of existing approaches and their limitations.We also identify a number of future research opportunities,which will hopefully guide the design of next generation solutions.

Implantable Electrochemical Microsensors for In Vivo Monitoring of Animal Physiological Information

In vivo monitoring of animal physiological information plays a crucial role in promptly alerting humans to potential diseases in animals and aiding in the exploration of mechanisms underlying human diseases.Currently,implantable electrochemical microsensors have emerged as a prominent area of research.These microsensors not only fulfill the technical requirements for monitoring animal physiological information but also offer an ideal platform for integration.They have been extensively studied for their ability to monitor animal physiological information in a minimally invasive manner,characterized by their bloodless,painless features,and exceptional performance.The development of implantable electrochemical microsensors for in vivo monitoring of animal physiological information has witnessed significant scientific and technological advancements through dedicated efforts.This review commenced with a comprehensive discussion of the construction of microsensors,including the materials utilized and the methods employed for fabrication.Following this,we proceeded to explore the various implantation technologies employed for electrochemical microsensors.In addition,a comprehensive overview was provided of the various applications of implantable electrochemical microsensors,specifically in the monitoring of diseases and the investigation of disease mechanisms.Lastly,a concise conclusion was conducted on the recent advancements and significant obstacles pertaining to the practical implementation of implantable electrochemical microsensors.

Exogenous calcium enhances the physiological status and photosynthetic capacity of rose under drought stress

Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related properties of rose under polyethylene glycol 6000(PEG6000)-induced drought stress.Chlorophyll levels,as well as leaf and root biomass,were significantly reduced by drought;drought also had a major effect on the enzymatic antioxidant system and increased concentrations of reactive oxygen species.Application of exogenous Ca^(2+)increased the net photosynthetic rate and stomatal conductance of leaves,enhanced water-use efficiency,and increased the length and width of stomata following exposure to drought.Organ-specific physiological responses were observed under different concentrations of Ca^(2+).Application of 5 mmol·L^(-1)Ca^(2+)promoted photosynthesis and antioxidant activity in the leaves,and application of 10 mmol·L^(-1)Ca^(2+)promoted antioxidant activity in the roots.Application of exogenous Ca^(2+)greatly enhanced the phenotype and photosynthetic capacity of potted rose plants following exposure to drought stress.Overall,our findings indicate that the application of exogenous Ca^(2+)enhances the drought resistance of roses by promoting physiological adaptation and that it could be used to aid the cultivation of rose plants.

Physiological Response Mechanism and Drought Resistance Evaluation of Passiflora edulis Sims under Drought Stress

In order to explore the response mechanism of Passiflora edulis Sims to drought stress,the changes in morpho-logical and physiological traits of Passiflora edulis Sims under different drought conditions were studied.A total of 7 germplasm resources of Passiflora edulis Sims were selected and tested under drought stress by the pot culture method under 4 treatment levels:75%–80%(Control,CK)of maximumfield water capacity,55%–60%(Light Drought,LD)of maximumfield water capacity,i.e.,mild drought,40%–45%(Moderate Drought,MD)of max-imumfield water capacity,i.e.,moderate drought and 30%–35%(Severe Drought,SD)of maximumfield water capacity,i.e.,severe drought.On the 40th day of drought treatment,13 indices,including seedling growth mor-phology,physiology,and biochemistry,were measured.The results showed that under drought stress,the height and ground diameter of P.edulis Sims gradually decreased with increasing drought stress,and there were signifi-cant differences in seedling height and ground diameter among the treatments.Drought stress significantly inhib-ited the growth of seven P.edulis Sims varieties.The contents of soluble sugar(SS),soluble protein(SP),proline(Pro),and other substances in P.edulis Sims basically increased with increasing drought stress.With the aggrava-tion of drought stress,the malondialdehyde(MDA)content of P.edulis Sims tended to increase to different degrees,the superoxide dismutase(SOD)activity and peroxidase(POD)activity both tended to increase atfirst and then decrease,and the change in catalase(CAT)activity mostly showed a gradual increasing trend.The con-tents of endogenous hormones in P.edulis Sims significantly differed under different degrees of drought stress.With the aggravation of drought stress,the abscisic acid(ABA)content of P.edulis Sims tended to increase,whereas the contents of gibberellin(GA),indoleacetic acid(IAA),and zeatin nucleoside(ZR)exhibited a down-ward trend.A comprehensive evaluation of the drought resistance of seven P.edulis Sims varieties was conducted based on the principal component analysis method,and the results showed that the drought resistance decreased in the order XH-BL>XH-TWZ>TN1>GH1>ZJ-MT>LP-LZ>DH-JW.

Physiological Analysis of Drought Resistance of Seven Cultivars Spring Wheat in Northern Regions of China

In order to determine the physiological mechanism of drought resistance of northern wheat in China,six drought resistant wheat and one sensitivity to drought wheat were planted in pots.They were subjected to drought treatment and normal water when the plants grew to the 3-leaf stage.Samples were collected at 10,20,30,and 40 days after the drought treatment,respectively.The electrical conductivity,photosynthetic parameters,chlorophyll fluorescence parameters,sugar content,proline content,protein content,and active oxygen scavenging enzyme activity of the plants were detected,and the agronomic traits of the wheat varieties were investigated at maturity.The results indicated that the phenotype and yield-related factors of Darkhan 144 changed little under the drought stress.The relative electrical conductivity of Kefeng 6 and Darkhan 166 was lower under the drought stress,and their cell membrane was less damaged.The Darkhan 144 and Darkhan 166 had higher drought resistance coefficients,and were the wheat varieties with stronger drought resistance.However,the physiological mechanisms of drought resistance of these three wheat were different:Darkhan 144 maintained a higher photosynthetic activity under the drought stress;Darkhan 166 maintained a higher protein content,photosynthetic activity and active oxygen scavenging enzyme activity.In addition,other drought-resistant varieties Kefeng 6,Kefeng 10 and Longmai 26 had a higher content of osmoregulatory substances under the drought stress.

Physiological and Transcriptome Analysis Illuminates the Molecular Mechanisms of the Drought Resistance Improved by Alginate Oligosaccharides in Triticum aestivum L.

Alginate oligosaccharides(AOS)enhance drought resistance in wheat(Triticum aestivum L.),but the definite mechanisms remain largely unknown.The physiological and transcriptome responses of wheat seedlings treated with AOS were analyzed under drought stress simulated with polyethylene glycol-6000.The results showed that AOS promoted the growth of wheat seedlings and reduced oxidative damage by improving peroxidase and superoxide dismutase activities under drought stress.A total of 10,064 and 15,208 differentially expressed unigenes(DEGs)obtained from the AOS treatment and control samples at 24 and 72 h after dehydration,respectively,were mainly enriched in the biosynthesis of secondary metabolites(phenylpropanoid biosynthesis,flavonoid biosynthesis),carbohydrate metabolism(starch and sucrose metabolism,carbon fixation in photosynthetic organisms),lipid metabolism(fatty acid elongation,biosynthesis of unsaturated fatty acids,alpha-linolenic acid metabolism,cutin,suberine and wax biosynthesis),and signaling transduction pathways.The up-regulated genes were related to,for example,chlorophyll a-b binding protein,amylosynthease,phosphotransferase,peroxidase,phenylalanine ammonia lyase,flavone synthase,glutathione synthetase.Signaling molecules(including MAPK,plant hormones,H_(2)O_(2) and calcium)and transcription factors(mainly including NAC,MYB,MYB-related,WRKY,bZIP family members)were involved in the AOS-induced wheat drought resistance.The results obtained in this study help underpin the mechanisms of wheat drought resistance improved by AOS,and provides a theoretical basis for the application of AOS as an environmentally sustainable biological method to improve drought resistance in agriculture.

Population genomic data reveal low genetic diversity,divergence and local adaptation among threatened Reeves's Pheasant(Syrmaticus reevesii)

Population genomic data could provide valuable information for conservation efforts;however,limited studies have been conducted to investigate the genetic status of threatened pheasants.Reeves’s Pheasant(Syrmaticus reevesii)is facing population decline,attributed to increases in habitat loss.There is a knowledge gap in understanding the genomic status and genetic basis underlying the local adaptation of this threatened bird.Here,we used population genomic data to assess population structure,genetic diversity,inbreeding patterns,and genetic divergence.Furthermore,we identified candidate genes linked with adaptation across the current distribution of Reeves’s Pheasant.The present study assembled the first de novo genome sequence of Reeves’s Pheasant and annotated 19,458 genes.We also sequenced 30 individuals from three populations(Dabie Mountain,Shennongjia,Qinling Mountain)and found that there was clear population structure among those populations.By comparing with other threatened species,we found that Reeves’s Pheasants have low genetic diversity.Runs of homozygosity suggest that the Shennongjia population has experienced serious inbreeding.The demographic history results indicated that three populations experienced several declines during the glacial period.Local adaptative analysis among the populations identified 241 candidate genes under directional selection.They are involved in a large variety of processes,including the immune response and pigmentation.Our results suggest that the three populations should be considered as three different conservation units.The current study provides genetic evidence for conserving the threatened Reeves’s Pheasant and provides genomic resources for global biodiversity management.

Irrigated Agriculture Facing the Challenge of Climate Change: Adaptation Strategies for Farmers in the Irrigated Perimeters of Môle Saint-Nicolas, Haiti

Môle Saint-Nicolas, like all other communes in the Republic of Haiti, faces increasing climate variability, impacting agricultural production and water resources. Consequently, there is a pressing need for adaptation to these climatic changes. This research aims to showcase the adaptation strategies deployed by farmers to cope with the increasing climate variability. Surveys were conducted through group and individual discussions with a randomly selected cohort of 150 farmers. Two types of analysis were performed: quantitative and qualitative. The quantitative data analysis was conducted using Statistical Package for the Social Sciences (SPSS) software. The findings reveal that farmers have perceived changes in rainfall patterns, temperature, wind, and their environment. These changes manifest as irregular rainfall, higher temperatures, prolonged drought periods, violent winds accompanied by rain, premature cessation of rains, and reduced flow from water sources. In response, the most common adaptation strategies adopted include selecting new cultivars, early-maturing varieties, crop rotation and diversification, canal dredging, new soil preparation methods, upstream water source protection, and micro-watershed management. The significance of this research lies in its contribution to enhancing farmers’ adaptive capacities by alerting stakeholders in the irrigated perimeters about the consequences of climate change, thereby incorporating the real needs of farmers in future projects.

The ABA synthesis enzyme allele OsNCED2^(T)promotes dryland adaptation in upland rice

Upland rice shows dryland adaptation in the form of a deeper and denser root system and greater drought resistance than its counterpart,irrigated rice.Our previous study revealed a difference in the frequency of the OsNCED2 gene between upland and irrigated populations.A nonsynonymous mutation(C to T,from irrigated to upland rice)may have led to functional variation fixed by artificial selection,but the exact biological function in dryland adaptation is unclear.In this study,transgenic and association analysis indicated that the domesticated fixed mutation caused functional variation in OsNCED2,increasing ABA levels,root development,and drought tolerance in upland rice under dryland conditions.OsNCED2-overexpressing rice showed increased reactive oxygen species-scavenging abilities and transcription levels of many genes functioning in stress response and development that may regulate root development and drought tolerance.OsNCED2^(T)-NILs showed a denser root system and drought resistance,promoting the yield of rice under dryland conditions.OsNCED2^(T)may confer dryland adaptation in upland rice and may find use in breeding dryland-adapted,water-saving rice.